Alluvial-transported soil, Biology

Assignment Help:

Alluvial

Materials of this catego~ya re deposited by running water in the form offroodplains, river terraces, deltas and alluvial fans. These deposits have two outstanding characteristics by, which they can usually be recognised with ease. Fit, the individual particles tend to be rounded and smootlfed by the action of running water. Second, the layers are usually distinct in that each contain particles of a particular range or size class depending upon the speed of the transporting water. Coarse materials are laid by swift water currents, whereas, fine particles are deposited by relatively calm waters.

Alluvial soils are found bo~deringri vers and slow moving bodies of water. When first formed; these deposits are sa low that they are frequently flooded at high-water stages, and at such times they receive additional increments of fine sediment, especially if they are well vegetated. At this stage of development, they are called flood plains. As the stream cuts its channel deeper, the flood plain is left above the reach of high water and is called a terrace. Large streams are frequently bordered by a series of terraces, the oldest being at considerable heights above the present water level.

Where streams enter a lake or a sea, the deposit of silt and clay that settles down at the edge of the still water may build a delta which gradually lengthens until it extends beyond the mouth of the stream. The Sunderbans in West Bengal and Bangladesh are examples of deltas, which supprt mangrove type of vegetation. Alluvial fans are formed where a stream descends from uplands, and a sudden change in gradient may sometimes occur as the stream emerges at the lower level. Deposition of sediments is thereby forced, giving rise to alluvial fans. They differ from a delta in their location and in the character of their debris. Fan material is often gravel and stony in nature
and is well drained.

Among the transported soils, the alluvial soils of the Indoagetic Plains are highly productive and have been under'cultivation for several thousands of years. The parent material of the Indo-Gangetic alluvial soils is actually in the Himalayas. Mountain and hill washes contribute huge quaiitities of sediments brought down by the rivers and deposited in the plains below. Most of the alluvial soils are under intensive crop cultivation.


Related Discussions:- Alluvial-transported soil

What are the three periods into which interphase, Q What are the three peri...

Q What are the three periods into which interphase are divided? Interphase is the preceding phase to the mitotic division. It is divided into three periods, G1, S and G2 the le

Need help, Many endangered plant species are currently being propagated by ...

Many endangered plant species are currently being propagated by commercial growers and botanical gardens and the sold (as both plants and seeds) to government agencies. Conservatio

Echinococcosis (hydatidosis), Echinococcosis (hydatidosis) Echinococco...

Echinococcosis (hydatidosis) Echinococcosis, also called hydatidosis, is a global problem particularly in countries where sheep and cattle raising forms the major animal husba

Homo sapiens sapiens (modern man), Hom o sapiens sapiens (MODER N MA...

Hom o sapiens sapiens (MODER N MAN) - Developed from Cro-Magnon about 10,000 years ago after last glacial period in the regions of Caspian and Mediterranean seas.

What is malnutrition, What is malnutrition? Malnutrition can be defined...

What is malnutrition? Malnutrition can be defined as a pathological condition resulting from a relative or absolute deficiency or excess of one or more of the essential nutrien

What er the parafunctional habits, What er the Parafunctional Habits P...

What er the Parafunctional Habits Parafunctional Habits like bruxism and clenching create mechanical and biological problems due to overloading and are considered to be one of

Of which main compounds is the mitochondrion structure made, Of which main ...

Of which main compounds is the mitochondrion structure made? Mitochondria are organelles delimited by two lipid membranes. The inner membrane invaginates to the interior of the

Why fats, Why Fats, Oils and Sugar are important for human body? This g...

Why Fats, Oils and Sugar are important for human body? This group imparts flavour to the items and thereby improves the palatability. Items incorporating them do melt in the mo

What is homocystinuria, Q. What is Homocystinuria? Homocystinuria may r...

Q. What is Homocystinuria? Homocystinuria may result from errors of methionine metabolism. This produces defects in the function of cystathionme b synthase or 5-mcthyltctrahyd

State about the importance of potassium, State about the importance of Pota...

State about the importance of Potassium  Potassium is the third major element required for plant growth, generally absorbed as K + ion. In soil 95 to 99 percent of potassium e

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd